Fuse cabinet



Jan. 24, 1939. A. CORBETT 2,145,155

Q FUSE CABINET Original Filed Feb. 5, 1956 2 Sheets-Sheet 1 ATTORNEYSJan. 24, 1939. 1 CORBETT' 2,145,155

FUSE CABINET Original Filed Feb. 5, 1936 2 Sheets-Sheet 2 i 11. a L-i zz4 z? z4 l-Y'g'.lr

v INVENTOR .ZM

ATTORNEYS Patented Jan. 24, 1939 UNITED STATES 2,145,155 FUSE CABINETAlfred Corbett, Irwin, Pa.., assignor to National Electric ProductsCorporation, a corporation of Delaware Application February 5, 1936,SerialNo. 62,448 Renewed July 1, 1938 1 Claim.

ance when the cabinet door is open. I have also;

made such modification in elements of the fuse socket mounting that thecover plates for the fuse sockets are freely liftable from mountedposition to give access to electrical connection carried by the mountingstructure which carries the fuse sockets and supports the cover plates;and have made the socket cover elements so to cooperate with the fusesockets that they are usable either with standard fuse sockets or withtamper-proof fuse sockets. Also, I so form and arrange the meanscarrying the electrical conductors, and other electrical connections,that they form in the fuse cabinet a built-up structure, which isreadily assembled, and which is peculiarly adapted to the mounting oftamperproof fuse sockets; and so form the body of the cabinet that itmay conveniently be built into a Wall in any locality thereof.

In the drawings:

Fig. I is a front elevation of the fuse cabinet with the fuse socketstructures mounted therein, the door of the cabinet being shown open toexpose the cover plates of the fuse socket mounting.

Fig. H is a. top plan view of a fuse socket cover plate forming. anelement of the fuse socket mounting.

Fig. III is a longitudinal, vertical section through the cover plateshown in Fig. II, taken on the plane of the irregular section linelIIIlI of Fig. II.

Fig. IV is a bottom plan View of the cover plate shown in Figs. 11 andIII.

Fig. V is a front elevation of the fuse cabinet, with the true, orfixed, cover of the cabinet removed to expose the mounting structure forthe fuse sockets.

Fig. VI is a cross-sectional view taken on the plane of the section lineVIVI of Fig. V.

Referring particularly to Figs. V and VI of the drawings, referencenumeral l designates the body of a metallic fuse cabinet, which hasattached to opposite side Walls thereof channels 2 and has perforateprojected corner lugs 3, for mounting the cabinet in a wall. Theseperforate corner lugs 3 are projected in a plane parallel to the planeof the side wall channels, so that they provide for attachment of thecabinet to above, the mounting means comprise primarily (Cl. 247-21)structural members which present faces parallel to the channels. Thebottom wall, or floor,

of the cabinet body has therein key slots 4 for mounting the cabinet on,the surface of a wall.

As in my co-pending application referred to contoured tie blocks 5 ofinsulating material, which are attached to the floor of the cabinet.These insulating blocks 5 are spaced from each other in the assembly,and carry the bus bars 6-1 in bridging relation therebetween. Decks 1,carrying fuse sockets 8, fit in mounted position on adjacent blocks, andare. held to the blocks and to the bus bars each by an elongate screw 9which is threaded to a screw hole in the floor of; the cabinet.Considering each deck individually, its mounting screw 9 has its headlying within, and at the base of, a tubular post l0 projected upwardlyfrom the body of the deck. Tubular post I0 serves additionally as aninsulating bar-g rier between the sockets 8. Center-contact screws H, atthe base of each of the sockets or shells 8, are projected through thedeck, and beneath the deck carry washers I2 which make contact with thebus bars 6 in intervals between insulating tie blocks.

It may here be observed that the decks l, and other parts which are ofinsulating material, are shown in the drawings sectioned to indicatethat they are composed of porcelain. It is to be understood, however,that they may be made" of a phenol condensation product, or some othersuitable molded material having insulating qualities.

In the cabinet assembly, referring specifically v to Fig. v of thedrawings, blocks l3 and M of insulating material carry connectionterminals for the fuse sockets, and are attached individually to thefloor of the cabinet.

Each of decks 1 which, as shown in Fig. V, is in plan view of elongaterectangular form, has at the corners thereof upwardly extendingpedestals l5, which support the cover plates I6 of the assembly.Considering individually one of the cover plates I6 for the fusesockets, this element, is rectangular in form, conforming in shape andsize to the deck I on which it is mounted, and has therein a pair ofcircular openings l1 giving access to the fuse sockets or shells 8.

Referring now particularly to Figs. II, III and IV of the drawings, itwill be seen that the cover plate l6 has an interfitting with itsassociated deck 1 by means of a central dependent boss l8, which isadapted to enter the tubular post it on deck 1; and that there are inthe under face of the cover plate diagonally disposed circular re-"cesses, or indentations, 19 adapted to receive matching pins 20projected upwardly from two ;of the pedestals 15. When placed on itsdeck,

ment with the deck of a nature to prevent displacement of the coverplate in the horizontal plane.

It will be seen in Figs. II and III of the drawings that the upper faceof the cover plateis formed marginally to provide a shoulder 2|. The

true cover 22 of the cabinet is dished inwardly at an opening therein,and this dished region 23 of the cover, surrounding the opening,terminates marginally in a horizontal trim 23a, which overlies andengages the cover plate at the marginal shoulder 2| thereof. Thismarginal engagement of the cover plate I6 and the true cover 22 of thecabinet, by preventing vertical displacement of each cover plate fromits associated deck, permits adequately firm assembly to be made withoutfixed attachment of the cover plate to the deck.

Because of the cooperative mounting of the cover plates, they may simplybe lifted from position on their associated decks, to permit work to bedone on the fuse sockets or shells 8, upon first removing the true cover22 of the cabinet. This true cover is itself normally fixed on the bodyI of the cabinet by means of screws 24, passing through screw holes 25in the cover and engaging lugs 26 in the body of the cabinet. Thecabinet door 21 is hinged to the true. cover 22, and when swung openexposes merely the cover plates iii of the assembly, and plug fusesinserted in the sockets 8. The appearance of the cabinet is thus neatand attractive when the door 21 is swung open to change fuses.

Referring particularly to the fuse sockets of the assembly, sockets oftwo differing types are shown associated in conjunction in the cabinet.As shown in Figs. I and V, two of the fuse sockets 8, which aredistinguished byreference letter a, are of common unspecialized type,while the other two fuse sockets, distinguished by reference letter b,are of tamper-proof type. The tamper-preventing structures of theselatter fuse sockets are, for increased clarity of illustration, omittedfrom Fig. VI of the drawings which is taken on a plane intersectingthem.

In order that fuse sockets of the tamper-proof type may be selectivelyadapted to fuses of but one selected capacity, they are made of sizesdiffering for different capacity circuits protected by fuses ofappropriate capacity inserted in the sockets. In the drawings, thesockets distinguished by reference letter Z) are. of lesser diameterthan the sockets distinguished by reference letter a. The cover platesit are so made that each of them may appropriately be used with a deckcarrying sockets of either diameter.

Referring to Figs. II, III, and IV of the drawings, it will be seen thateach of the circular openings l'l through the cover plate has achamfered rim 28 formed in the under face of the cover plate. If then ascrew shell of greater diameter lies under the cover plate, theuppermost bodily formed'bulge, or thread, of the shell lies in thechamtfer 28 barely to expose the interior jof the shell for theinsertion of a plug fuse therein. With a socket of the larger diameter,the extreme edge of the socket thus is directly in line with the upperwal1. line of the opening. If the shell be of a slightly lesserdiameter, the extreme edge of the shell lies slightly, andconcentrically, within the upper wall line of the opening. with theuppermost bodily bulge, or thread, of the shell filling the spacebetweenthe extreme edge of the shell and the wall line of the opening throughthe cover plate.

Because of this conformation of the openings through the cover plate,the same cover plate may be used on decks carrying sockets of slightlydiffering diameter. This is because the chamfer 28 permits the bulge ofthe uppermost thread on the larger diameter socket so to lie that'it isout of actual interfering contact with the cover plate, while with thelesser diameter socket no space which might receive dust and dirtintervenes between the shell and the wall of the opening through thecover plate. It may readily be understood that, because of the veryslight tolerance permitted in the diameter of the openings, the accuratepositioning of the cover plate, effected by the engagement of boss [8 intubular post Ill, and of deck-carried pins 20 in .cover plate recesses19, becomes a matter of primary importance.

Between the openings I! through the cover plate there is a shapeddepression 29, from which a screw hole 38 extends downwardly into theboss l8. This arrangement is adapted to receive and secure a platebearing in condensed form identifying data as to the fuses which are tobe received in the'associated sockets, or as'to the circuits to beprotected by the fuses.

The fuse cabinet as a' whole is, as may be seen from Fig. I of thedrawings, of particularly pleasing appearance even when the cabinet doorlies in open position exposing the dished region of the true cover ofthe cabinet, and the upper face of "the fuse mounting assembly in thecabinet. The fuse socket arrangement and :mounting is such as to providea maximum of simplicity, convenience, and circuit protection, and onewhich is peculiarly'adapted to the use of tamper-proof fuse sockets. Inthis latter connection it should be noted that the use of individualsocket-carrying decks, and individual terminal-carrying blocks,.readilypermits the building up within the cabinet of an assembly comprisingfuse sockets of differing size, or formation, adapted to receive fusesof variant capacity.

Considering the cabinet itself, the provision of lath-receiving.channels on opposite side walls of the cabinet body, and the provisionof perforated lugs on all four corners of the cabinet body, permits itto be built into a wall in any locality'thereof. That is, in an intervalbetween studding'members, the lugs may be used to attach'the cabinet toboth adjacent studding members, while receiving the endsiof the lathesevered to permit insertion of the cabinet in the channels carried byits side walls if the positioning of the. studding members so permits.Otherwise considered, the channel and lug arrangement permits attachmentof the cabinet to a single studding member lying to either side of thecabinet.

I claim as my invention:

In a fuse cabinet primarily comprising a hollow rectangular body havinga floor and upstanding side walls and a cover applicable to thecabinetbody to overlie'the same, outwardly open channels extended along two"opposed side walls of the cabinetbody to embrace structural alplaneparallel to the plane of the adjacentside wall channel to provideattachment to structural members presenting for attachment of thecabinetsurfaces parallelto the channels.

ALFRED .CORBETT.

